Alternative lymphatic pathway after previous axillary node dissection in recurrent/primary breast cancer.

Objectives: The sentinel lymph node approach has almost become the standard procedure of choice in the management of patients with early breast cancer. The status of sentinel nodes, whether or not pathologically involved by cancer cells, represents those of the axillary nodes with a negative predictive value of almost 100%. If the axillary lymphatic nodal drainage is altered, alternative lymphatic pathways and accordingly sentinel node location will be changed. Methods: In this article, 4 patients are presented, 3 with recurrent breast cancer who had already undergone lumpectomy, axillary node dissection, and radiotherapy in the past and 1 with primary breast cancer after surgical removal of a malignant melanoma on her back and had axillary node dissection on the same side as the breast cancer. These patients underwent lymphoscintigraphy followed by sentinel node localization using the gamma probe and also blue dye injection during surgery. Results: All patients showed alternate lymphatic pathways, 1 had an ipsilateral internal mammary node and crossed lymphatics to a contralateral axillary node, 2 had intramammary sentinel nodes, and 1 had an internal mammary on the same side. Pathologic examination of the intramammary and contralateral sentinel nodes were negative for metastases. Internal mammary sentinel nodes were not biopsied. Conclusion: We feel that sentinel node lymphoscintigraphy should be done even in patients who have altered lymphatic pathways resulting from previous axillary node dissection. It allows identifying and biopsy of the sentinel node at its new unpredicted location.